216897685 has 8 divisors (see below), whose sum is σ = 262150560. Its totient is φ = 172269264.

The previous prime is 216897671. The next prime is 216897691. The reversal of 216897685 is 586798612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216897685 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155347 + ... + 156736.

It is an arithmetic number, because the mean of its divisors is an integer number (32768820).

Almost surely, 2^216897685 is an apocalyptic number.

It is an amenable number.

216897685 is a deficient number, since it is larger than the sum of its proper divisors (45252875).

216897685 is a wasteful number, since it uses less digits than its factorization.

216897685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312227.

The product of its digits is 1451520, while the sum is 52.

The square root of 216897685 is about 14727.4466558192. The cubic root of 216897685 is about 600.8300410052.

The spelling of 216897685 in words is "two hundred sixteen million, eight hundred ninety-seven thousand, six hundred eighty-five".